I have a 2015 two door with 2.5" Rock Krawler max travel with 35" trail grapplers. Rides great at city speeds and on the highway up to about 65. At 70 I get a shimmy. It feels like a tire balance issue but I have just had them re balanced and all good. Thoughts on what to check next?

 

Work your way up. Check ball joints, tie rod ends, and drag link ends, track bar at frame and axle, play in unit bearings, bad u joints, torque on all bolts in control arms.

You running stock drive shaft?

 

Swap your front and rear tires. If the shimmy changes then you know it's the wheels/tires. If it doesn't you need to look at driveline and steering.

In my experience any speed sensitive shimmy or wobble has always been a tire/wheel issue

 

Go up to the JK Write-Ups area. There is a diagnosis thread by Planman stuck right to the top...

 

X2 (10 char)

 

Thanks guys. I know the planman writeup on wobbles. I have checked everything and all tight and good. The jeep only has 8k miles. I will try tires again.

 

I have a 2012 two door with a 2.5" Rubicon Express lift with 35" trail grapplers. I didn't have castor correction when I first lifted the Jeep but it drove perfectly fine with the stock BFG KOs. When I upgraded to a used set of the Nittos it had a very noticable wobble at around 70-80km/h. I upgraded my track bars to Adjustable JKS track bars and that helped a lot with the "flighty" steering feeling but I still had the same wobble. I did a 5 tire rotation and had no change in the wobble at that speed.

This spring I got gussets and a truss installed and to save some cash on the alignment I got some RE Geometry correction brackets. That moved my castor back to the 5-6 range and corrected the wobble problem completely.

I will eventually get better control arms but for now the brackets help a lot.

 

Thanks. I do have a full set of Rock Krawler control arms and have the caster dialed in to about 6. I hope to try rotating and see if that helps. The tires have about 6k on them and have been rotated once.